Effects of Fine Grid NO2 Modeling around a Thermal Power Station: A Case Study

Objective: The objective of this study was to assess the outcome of fine grid modeling on top of a courser grid to predict the NO2 concentration more accurately in an airshed and at sensitive receptors. Methods: This study assessed the cumulative NO2 impact of all major emission sources in an airshed using USEPA regulatory model AERMOD. A 50 km by 50 km airshed is considered in the study. Micro-environmental pollution was modeled using a refined grid analysis. An area (4 km x 4 km) close to GTPS, with receptors at every 150 m apart and a further fine grid (500 m x 500 m) with receptors at every 50 m apart, was modeled. Results: Coarse grid modeling showed annual average NO2 concentration levels within applicable standards. However, when fine grid modeling was conducted, the predicted annual average NO2 concentration levels were found to exceed World Bank Guidelines and Bangladesh Standards. A source contribution analysis showed that a quick rental power plant (natural gas generators) without proper stacks contributed a significant portion of the maximum 1-hr and annual average NO2 concentration (76% and 86%, respectively). Conclusion: The findings of fine grid modeling can be used at the policy level of the government to enforce environmental regulations on the minimum height requirements of stacks and city planning, avoiding downwind directions and the close proximity of powerplants to safeguard human health.

Natural Resources for Sustainable Water Treatment - A Review

Background: Purification and remediation of water remain to be a mammoth challenge for environmental engineers, continuously mounting pressure on providing safe water for consumers. Nevertheless, care has to be taken to avoid chemicals in treatment, which could prove to be toxic. One of the most prominent stages in treating water for human consumption is clarification through coagulation and flocculation to remove colloidal particles including silt, clay, precipitated iron or manganese oxides along with bacteria and algae. Objective: In order to achieve sustainability, the only possible way is to use innate materials in combination with inherent technologies. Considering this, the present review will appraise the efficiency of natural coagulants in treating surface water. Several researchers have tested numerous natural coagulants for clarification of water. Nevertheless, information on various natural coagulants and their efficiency has not yet been presented. Methods: Hence, an attempt is made to bring about a comprehensive account of various natural coagulants and also to understand their properties and efficiencies in treating water. Results: Cumulative information regarding natural coagulants presented in this review will add to the database of natural coagulants and can be adopted at various temporal and spatial levels according to the availability of these coagulants to treat water. Nevertheless, precise research on coagulation parameters and shelf life of treated water will enhance the opportunities for point of use water treatment technologies. Conclusion: The current review presents natural coagulants having the potential to treat surface water as sustainable alternatives to point of use treatment.

A Backward Scenario Planning Overview of the Greenhouse Gas Emission in Iran by the End of the Sixth Progress Plan

Taking Iran as the 7th Greenhouse Gas (GHG) emission source of the world, the country contains a high potential for the emission management plans and studies. As the economy is a significant factor in the greenhouse gas emission, studying the economy and GHG emission integrated relations must be taken into account of every climate change and environmental management plan. This paper investigates the relationships among the economic, demographic, foreign policies, and many other domestic and foreign parameters, which are illustrated by sixth Iranian document over development and GHG emission in three progress scenarios made for this plan. In this paper, all the significant GHG emissions such as CO₂, SO₂, NO_x, hydrocarbons, and CO in the period of 2014-2020 are being studied. As the results show, the number of emissions is directly related to domestic and foreign parameters, which means a better economic status in Iran causes an increase in the number of emissions. The foreign policies are more effective in the Iranian economy and emissions than the domestic policies and parameters. The scenarios and the results show that the Iranian economy and energy systems have a significant potential for efficiency development plans. However, one thing is clear that Iranian emissions will be increased to 800 million tons by the end of the plan period (by 2021). This significant increase in the amount indicates the importance of optimization and efficiency development plans in Iran, which is predicted to control and fix this increment around 3-4%.

A Mini Review of Technological Options for Disposal of Municipal Solid Waste in India

Background: It has been seen that 90% of municipal solid waste is disposed off in open dumps and landfill sites, causing problems for the environment, and public health in developing countries. Many technological options can convert waste into various forms of energy. Heat and electricity can be generated and utilized for specific thermodynamic conversion processes and different types of biofuel can also be extracted from the organic municipal solid waste. Objective: This study evaluates the different treatment options available to convert waste into energy, and also concludes its environmental aspect with suggestions, which may be beneficial for encouraging the researchers to work for further improvement in this aspect. Methods: For each technological area, results from the literature review and the different expert opinions were considered to provide an analysis of the treatment technology, identify the internal and external environmental threats and important gaps in treatment technologies for MSW in India. Results: It has been observed from various studies that the pyrolysis/gasification is the suitable option for the treatment of different compositions of solid waste with high energy recovery in India, while bio-methanation is suitable for a decentralized system with a high energy value, and a minimum level of pollution & health hazards. Conclusion: The study and observations show that there are multiple technological options for the treatment of municipal solid waste. Research and development in the MSW sector is not a priority in India, therefore, it has been recognized that expert research advice is required while selecting technology as well as for deciding the tools and techniques to handle this issue.

The Growth of Triticale (Triticosecale wittm.) in Multi-Metal Contaminated Soils by Use of Zeolite: A Pilot Plant Study

Background: Heavy metals are the most common form of environmental pollution and the evaluation of heavy metal contaminated soils is necessary for reducing the associated risks, making the land resource available for agricultural production, and enhancing food security. There are 2,000 contaminated sites in Greece, according to a previous survey report issued by the Greek Ministry of Environment, out of which 300 required immediate restoration. Objective: This study investigated the effects of Cd, Pb, and Zn on Triticale (Triticosecale wittm.) growth in an above-referenced multi-metal contaminated site. Methods: In order to evaluate Triticale growth in metal contaminated soil, Triticale plants were cultivated in pots filled with unpolluted and metal-polluted soils in the absence/ presence of Zeolite as an agent empowering the restoration of pollution and immobilizing heavy metals. Results: The results showed that the Triticale plant in polluted soils with high metal concentrations, namely 4.34, 295 and 1,467 mg/kg for Cd, Pb, and Zn, respectively, can act as a “moderate” accumulator of Zn and as a “weak” accumulator of Pb and Cd; while the presence of 1% Zeolite in multi-metal-polluted soils can significantly contribute to plant growth by limiting the uptake of Cd, Pb, and Zn. Conclusion: This study demonstrated that the addition of 1% Zeolite to multi-metal contaminated soils could minimize metal (Pb, Cd, and Zn) pollution in the environment and positively contribute to the growth of Triticale biomass for use as an animal feed within the context of sustainable development.

The water industry and decarbonisation of cities: A review

: The urban water industry is a very energy intensive industry. Higher water quality standards are driving a level of energy growth that is threatening to move it to the top rank. Climate change is further exacerbating this situation: Growing aridity is variously imposing an enhanced carbon burden through water recycling, trans-regional pipelines and desalination plants. Natural disasters too can often affect water quality requiring energy hungry mitigations. There’s clear evidence that a failure to appropriately weight energy considerations in water infrastructure is commonplace and that this is an unsustainable position for the industry and is prejudicial to working towards zero carbon cities. Real time tracking of CO2e emissions is an important starting point in raising operator consciousness and introducing rivalry between utilities in attaining abatement. So too is reaching out to the resource and manufacturing sectors to form strategic alliances as well as seeking to enter into closer relationships with the energy sector.

Composite Membrane and Evaluation on Separation Oil/Water

Background: The generation of wastewater contaminated with organic compounds, release or spill into these water bodies can lead to serious environmental problems. The removal of chemical pollutants in water presents itself as one of the central issues regarding the issue of environmental remediation. In this sense, membranes, haves gained increasing importance in the environmental area. Objective: This present study aims to develop a composite membrane using UHMWPE/LDPE/CTAC-HGC to be used for oil/water separation of wastewater effluents. Methods: The polymeric membrane and composite membrane were prepared by uniaxial dry compaction and sintering. Both hard green clay (HGC) and hard green clay organophilized with cetyl trimethyl ammonium chloride (CTAC-HGC) were characterized by X-ray Diffraction (XRD), infrared spectroscopy (IR) and scanning electron microscopy (SEM). UHMWPE, polymeric membrane and composite membrane were characterized by XRD and SEM. Result: The water flux through the composite membrane was evaluated using pure water as a permeate. The potential of the composite membrane to separate oil-water emulsions was tested. Conclusions: The composite membrane showed excellent removal of the oil, exhibiting removal of more than 99.60 %, evidencing the process of composite membrane separation as an alternative technology for the treatment of oil.

Thermal Activation of Brazilian Smectite Clay (Primavera) and its Application for the Removal of Cadmium from Aqueous Solution

Background: Region-based solutions for water cleaning could be critical to tackle the water challenges faced in enhancing the in the future. Brazilian Primavera clay is cheap, abundant, and an untested material that has the potential to be used for water cleaning. Objective: the objective of the present work was to thermally activate and characterize the Brazilian clay and then determine the potential to remove Cd2+ from an aqueous solution. Methods: Primavera clay was thermally activated at 300 oC and characterized using X ray diffraction, X-ray Spectroscopy Energy Dispersive, and N2 adsorption. Sorption equilibrium was determined using the following experimental conditions: constant pH 4.5, 5 h, and 27 oC. Langmuir, Freundlich, Dubinin-Radushkevich and Temkin isotherms models were applied in order to determine the efficiency of clay used as an adsorbent. Adsorption kinetics was analyzed using the pseudo-second-order kinetic model. Results: In this study, results revealed that even though the heat treatment did not cause profound alterations on the clay structure(smectite) and surface area (78 m2 /g), a pseudo-second-order kinetic constant of 0.5563 mg/g/min was found for the cadmium removal. Conclusion: The mathematical models of the Langmuir and Temkin showed a better fit to the experimental data. A high affinity between the cadmium and the thermally activated Primavera clay was found up to 88 % with removal efficiencies.